The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Oct. 04, 1994
Filed:
May. 01, 1992
Dennis J Denen, Columbus, OH (US);
John J Knittle, Westerville, OH (US);
Albert E Weller, III, Columbus, OH (US);
Hemostatic Surgery Corporation, Georgetown, KY (US);
Abstract
A power supply for use with resistively-heated surgical instruments is provided, wherein accurate temperature regulation is achieved employing a resistance feedback circuit. The power supply powers the surgical instrument with an AC voltage waveform, and applies a fixed, low level DC signal to the heating element to produce a DC signal proportional to the instantaneous resistance of the heating element. The DC signal is compared to a setpoint value to obtain a control signal for adjusting the power delivered to the instrument to maintain a substantially constant heating element temperature, even under varying thermal loads.